GF/wife "policeswoman effect"

This is what I call the phenomenon whereby men are considered more trustworthy when accompanied by a female. Most guys have probably had some version of the incident where you are going to your car in a parking garage late at night, and there is a lone woman going to her's, and she gives you a suspicious look and hurries to her car. Lots of other normal situations where women are more at ease when I'm with the gf. She says I have an "intimidating" look. I said "why don't I intimidate you - because you can see through to my erudition, generosity of spirit, and civilized demeanor?". She said "no, I can see through to your inherent evil." Had to pop her for that crack.

An example of this, and how it can backfire - a couple of guys persuaded a couple to give them a test drive on their yacht, pretending they wanted to buy it. They also had along one guy's visibly pregnant gf, which probabably made they look less suspicious. They tied the couple to an anchor and threw them overboard at sea.